In the manufacture of tissue products such as facial tissue, bath tissue, paper towels and the like, it is often necessary to change certain endless belts, such as through-air drying fabrics, on the papermaking machine when changing over to different products or grades. For example, when switching between making through-air dried bath tissues and towels, the through-air drying fabric typically needs to be changed each time a different product is to be made because the desired three-dimensional topography of each product is typically different. In order to change the fabric, the paper machine must be shut down, which results in several hours of machine down time and loss of productivity. Also, repeated shutdowns and start-ups of the machine and the attendant, and drop and rise in processing temperatures cause thermal cyclic fatigue to the through-air dryers, which ultimately necessitates a costly replacement.
In addition to changing fabrics to accommodate different grades of papermaking, fabrics need to be replaced periodically as they often wear or become brittle with age. Like the substitution of fabrics, replacement requires that the paper machine must be shut down, which results in several hours of machine down time and loss of productivity.
Therefore, there is a need to improve the process of changing papermaking belts so as to reduce machine down time, improve operating efficiency and avoid many of the problems associated with starting and stopping the papermaking machine.